Lunch box



FIG. 1 is a perspective view of a lunch box showing my new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a back elevation view thereof;

FIG. 4 is a left side elevation view, the right side elevation view being a mirror image thereof;

FIG. 5 is a top plan view thereof; and

FIG. 6 is a bottom plan view thereof; and,

FIG. 7 is an open state perspective thereof.

The broken lines in the drawings depict portions of the lunch box and form no part of the claimed design. 

CLAIM The ornamental design for a lunch box, as shown and described. 